package drawtest;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class SimpleCanvas
{
	  public void run() {
		    Display display = new Display();
		    Shell shell = new Shell(display);
		    shell.setText("Canvas Example");
		    createContents(shell);
		    shell.open();
		    while (!shell.isDisposed()) {
		      if (!display.readAndDispatch()) {
		        display.sleep();
		      }
		    }
		    display.dispose();
		  }

		  /**
		   * Creates the main window's contents
		   * 
		   * @param shell the main window
		   */
		  private void createContents(Shell shell) {
		    shell.setLayout(new FillLayout());

		    // Create a canvas
		    Canvas canvas = new Canvas(shell, SWT.NONE);

		    // Create a button on the canvas
		    Button button = new Button(canvas, SWT.PUSH);
		    button.setBounds(10, 10, 300, 40);
		    button.setText("You can place widgets on a canvas");

		    // Create a paint handler for the canvas
		    canvas.addPaintListener(new PaintListener() {
		      public void paintControl(PaintEvent e) {
		        // Do some drawing
		        Rectangle rect = ((Canvas) e.widget).getBounds();
		        e.gc.setForeground(e.display.getSystemColor(SWT.COLOR_RED));
		        e.gc.drawFocus(5, 5, rect.width - 10, rect.height - 10);
		        e.gc.drawText("You can draw text directly on a canvas", 60, 60);
				int xx = (int) (10+Math.random()*140);
				int yy = (int) (10+Math.random()*140);;
				e.gc.drawOval(xx, yy, 20, 20); 
		      }
		    });
		  }

		  /**
		   * The application entry point
		   * 
		   * @param args the command line arguments
		   */
		  public static void main(String[] args) {
		    new SimpleCanvas().run();
		  }
}
